This study proposes to demonstrate and evaluate the cost and effectiveness of methods of improving physician prescribing in a population of more than 5,000 physicians delivering care to ambulatory Medicad patients. The educational modalities proposed include: (1) an attractive mailer; (2) visits to inappropriate prescribers by (nonphysician) drug information specialists; and (3) a visit or telephone call to inappropriate prescribers by a practicing physician. These interventions are designed to reach those physicians whom earlier studies have identified as inappropriate prescribers. Nine discrete prescribing topics will serve as the subject matter vehicles for the proposed educational modalities. These topics represent an extremely wide range of the prescribing spectrum.